THURSDAY, Dec. 14, 2017 (HealthDay News) — Most children born with brain abnormalities caused by the Zika virus are facing severe health and developmental challenges at 2 years of age, a new study suggests.

These problems may include seizures, an inability to sit independently as well as problems with sleep, feeding, hearing and vision, according to researchers from the U.S. Centers for Disease Control and Prevention.

Their findings come from a study of 19 Zika-infected children in Brazil, the epicenter of a Zika outbreak that began in 2015.

Most of the children were found to have problems in multiple areas as a result of prenatal exposure to the mosquito-borne virus, the researchers reported.

“Children severely affected by Zika virus are falling far behind age-appropriate developmental milestones, and their challenges are becoming more evident as they age,” CDC Director Dr. Brenda Fitzgerald said in an agency news release.

All children exposed to Zika in the womb need continued monitoring to understand the full impact of the infection during pregnancy, Fitzgerald said.

Zika exposure during pregnancy can cause fetuses to develop microcephaly — an unusually small head for their age.

The virus affected thousands of children born in northern Brazil in 2015-2016. Microcephaly was the most devastating outcome, and scientists are only now learning what its long-term ramifications might be.

All 19 children in the study had microcephaly and confirmed Zika exposure. In their report, the CDC researchers and scientists at the Ministry of Health of Brazil documented complications the children experienced when they were 19 to 24 months old:

Eleven suffered seizures.

More than half had sleep problems.

Nine had feeding difficulties, such as trouble swallowing.

Hearing was a problem for 13 kids, with some unable to react to the sound of a rattle.

Eleven had vision problems.

Fifteen had severe motor impairments.

Complicating their care, 14 of the children had at least three of these challenges. Eight had been hospitalized, most often for bronchitis or pneumonia.

“As children born affected by Zika virus grow up, they will need specialized care from many types of health care providers and caregivers,” said Dr. Georgina Peacock, director of the CDC’s Division of Human Development and Disability.

“It’s important that we use these findings to start planning now for their long-term care and stay vigilant in Zika prevention efforts in the United States and around the world,” she said in the news release.

The findings are published in the Dec. 15 issue of the CDC’s Morbidity and Mortality Weekly Report.

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